Transgene expression by human CD34⁺ cells that were cultured in vitro for 14 days after immunobead selection from the chimeric mouse bone marrow. Immunobead-selected and cultured nontransduced X-CGD CD34⁺ cells served as negative control for gp91^phox (A) and CFP (D) expression, respectively. (B-C) Shown are representative analyses of gp91^phox expression of transduced MFGS-gp91^phox X-CGD CD34⁺ PBSCs and MFGS-CFP–transduced normal CD34⁺ PBSCs, respectively, in which gp91^phox transgene expression was detected in 10% of cells, and native gp91^phox expression was detected in 76% of cells. (E) Shown is a representative analysis of CFP transgene expression by MFGS-CFP–transduced normal CD34⁺ PBSCs in culture, in which CFP expression was detected in 24% of cells.